• The Plant Pathology Journal
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• v.23 no.2
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• pp.57-61
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• 2007

Whitefly-transmitted geminiviruses (WTGs) are economically important pathogens causing serious damage on tomato and chilli pepper in Indonesia. Geminiviruses are readily transmitted by its insect vector, sweetpotato whitefly (Bemisia tabaci). However, greenhouse whitefly (Trialeurodes vaporariorum), another species of whitefly, is commonly found together with B. tabaci in the field. Incidence of yellow leaf curl disease in tomato and chilli pepper is probably correlated with the population of whitefly complex. It is becoming important to find the role of T. vaporariorum in the spread of the disease. Therefore, research is conducted to study the characteristic relationship between tomato leaf curl begomovirus (ToLCV) and two species of whitefly. The two species of whitefly, B. tabaci and T. vaporariorum, was capable to transmit ToLCV although it was evidenced that B. tabaci is more effective as insect vector of ToLCV in tomato and chilli pepper. A single B. tabaci was able to transmit ToLCV to tomato with a minimum acquisition and inoculation access period of 10 h. Transmission of ToLCV by T. vaporariorum required at least 10 insects per plant with a minimum acquisition and inoculation access period of 24 h. The transmission efficiency will increase with longer acquisition and inoculation access period of the insect and the higher number of insect per plant.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.1
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• pp.75-78
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• 2001

The whitefly, Dialeuropora decempuncta Quaintance and Baker (Homoptera : Aleyrodidae) causing considerable damage to mulberry, Morus alba. Crop loss caused by the whitefly was estimated in mulberry. Quantitative yield loss was estimated on the basis of harvest data from both sprayed and unsprayed plots. Data on pest incidence has been recorded at weekly intervals in both sprayed and unsprayed plots from 30 th day of plant age till harvesting i.e., 60 days after pruning in August October season. An attempt has been made to establish a relationship between whitefly population and percentage of crop loss due to it. Percentage of crop loss due to whitefly has got a linear relationship with the whitefly population. An initial population of 24 adults/top leaf would be able to cause 24% loss (l,630 Kg leaf/ha ) in a period of 30 days. Economic analysis postulates that application of pesticide can stove a net amount of 1,630 Kg leaf/ha which is sufficient to produce 67.65 Kg of additional multivoltine cocoons. This determines the cost/benefit ratio which will enable to workout the economics of management practices.

• Current Research on Agriculture and Life Sciences
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• v.30 no.2
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• pp.115-123
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• 2012

Whiteflies harbor several secondary endosymbionts, which are maternally inherited from mother to offspring, that have major effects on host preferences, biology, and evolution. Here, we identified Wolbachia bacteria in sweetpotato whitefly (Bemisia tabaci) as well as whitefly popluations from other countries by comparison of 16S rDNA sequences. Wolbachia were detected in all tested indigenous B. tabaci populations (Bangladesh, Myanmar, Nepal, and the Philippines) as well as Q1 biotype of Korea, whereas they were absent from B biotype of Korea and Q biotype of China. Wolbachia were also detected in all five tested Aleurodicus dispersus populations as well as Tetraleurodes acaciae, whereas they were not detected in all seven Trialeurodes vaporariorum populatuions. In addiiton, Wolbachia were detected in parasitic wasp (Encarsia formosa) of B. tabaci as well as honeybee (Apis mellifera). Among the 19 whitefly populations from different countries, our analysis identified four phylogenetic groups of Wolbachia, thereby demonstrating the high diversity of this genus. Wolbachia phylogeny suggests a correlation of geographical range with ecological variation at the species level.

• Korean Journal of Agricultural Science
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• v.42 no.1
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• pp.7-13
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• 2015

Ninety genes randomly selected from tobacco whitefly (Bemisia tabaci) cDNA library was studied for selecting target gene in order to control of tobacco whitefly using TRV-VIGS vector (tobacco rattle virus-virus induced gene silencing vector) with RNAi. First of all, the occurrence of B. tabaci adult according to agro-infiltration of TRV was no significant difference. And that of TRV inserted tobacco whitefly cDNA showed a significant difference in each sample. P CV and N CV sample were more than 80% could be confirmed in 5 samples, for example, wh11, wh36, wh46, wh50 and wh71. Lastly, the occurrence of nymph and egg also showed a significant difference in each sample. That could be confirmed in 11 samples, for example, wh01, wh09, wh10, wh15, wh16, wh23, wh24, wh48, wh64 and wh66. In case of wh46, wh50 and wh71 sample could be confirmed that occurrence of B. tabaci adult was many, but occurrence of B. tabaci nymph and egg was a little. So sample showed a physioecological good effect to control of whitefly need to be investigated variation of gene expression in whitefly body using qRT-PCR through individual test.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.109-117
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• 2016

We investigated the control of Bemisia tabaci adults in tomato greenhouses using the eggplant as a trap plant with 4 systemic chemicals. The control effect of dinotefuran SG 50% on tobacco whitefly adults was 80% mortality, the highest than that cyantraniliprole, pyridaben and clothianidin, 51.0%, 12.4% and 11.0% respectively when all chemicals with recommended doses were used. Dinotefuran was applied at various doses and was observed to be most effective above 200ppm (88.4%)t. The control effect of dinotefuran lasted for appromimately nine 9 days and the density of tobacco whitefly adults increased there after. In field tests, the densities of tobacco whitefly adults on tomato shoots were highest at points 0, 15 and 20 m from the eggplant traps and lowest at 5 and 10 m. When the density of tobacco whitefly was low and the eggplants with dinotefuran SG 50% were placed in the tomato greenhouse at 10 m intervals, the overall density of tobacco whitefly adults was lower. In addition, densities were higher at the side of the greenhouse than in the interior and further away from the eggplant. When the density of tobacco whitefly was high and the eggplants with dinotefuran were placed at 5 m intervals, the density of tobacco whitefly at each 5 m point decreased. Theses results confirm that the eggplant is an effective trap plant for attracting tobacco whitefly audlts and combined with dinotefuran SG 50% decreases the density of tobacco whitefly in tomato greenhouses.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.65-71
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• 2000

A study was conducted to examine the relationship between abiotic factors and the population of white-fly (Dialeuropora decempuncta) in mulberry field. The study reveals that relationship between abiotic factors and the whitefly population is very much existent like other pests in other agricultural crops. Duration and time of distinct occurrence of whitefly in mulberry is influenced by the abiotic conditions of field. Abiotic parameters of previous month are more important in influencing the intensity of the pest than the current abiotic factors. Not all the abiotic factors are equally important but factors like minimum temperature, fluctuation in temperature during the days minimum relative humidity, fluctuation in relative humidity and rainfall are the major important lactors in influencing the intensity of the pest under consideration.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.427-439
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• 2023

The silverleaf whitefly, Bemisia tabaci, is a major pest distributing worldwide damaging over 900 host plant species, and is highly resistant to chemical pesti- cides. Due to the high pesticide resistance of whitefly, there is a need for alternatives to chemical control. Entomopathogenic fungi are candidates for biological pesticide that can overcome the resistance problem of chemical pesticide. Therefore, in this study, we tested pathogenicity of the entomopathogenic fungi to select high insec- ticidal activity against whitefly. As a result, IPBL-C (Cordyceps fumosorosea) and IPBL-F (Metarhizium pinghaense) isolates showed high insecticidal activity against whitefly. Additionally, as a result of culturing the selected isolates on spent coffee grounds medium, the conidia of IPBL-F produced on coffee grounds medium showed five times higher heat stability after heat treatment at 45℃ for one hour than conidia produced on PDA medium.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.1-7
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• 2014

The possibility of using hyphomycete fungi as suitable biocontrol agents against greenhouse whitefly has led to the isolation of various insect pathogenic fungi. Among them is Beauveria bassiana, one of the most studied entomopathogenic fungi. The objective of this study was to use B. bassiana M130 as an insecticidal agent against the greenhouse whitefly. M130 isolated from infected insects is known to be a biocontrol agent against greenhouse whitefly. Phylogenetic classification of M130 was determined according to its morphological features and 18S rRNA sequence analysis. M130 was identified as B. bassiana M130 and showed chitinase (342.28 units/ml) and protease (461.70 units/ml) activities, which were involved in the invasion of the host through the outer cuticle layer, thus killing them. The insecticidal activity was 55.2% in petri-dish test, 84.6% in pot test, and 45.3% in field test. The results of this study indicate that B. bassiana has potential as a biological agent for the control of greenhouse whitefly to replace chemical pesticides.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.207-215
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• 2003

This study was carried out to evaluate toxicities of 3 registered insecticides to greenhouse whitefly(GWF), Trialeurodes vaporariorum and sweetpotato whitefly(SWF), Bemisia tabaci, B-biotype. Insecticide activities were evaluated by testing systemic action, residual effect in the laboratory, and control efficacy in the greenhouse. All experiments were tested at the recommended concentration(RC), half and a quarter concentrations of RC of each insecticides. Acetamiprid showed 45%, 42% ovicidal effect to greenhouse whitefly and sweetpotato whitefly at 40 ppm, respectively. Acetamiprid showed more than 97% larvicidal activities on the 3rd instars larvae of GWF and SWF at the recommended and its half concentrations. On the adults of the two whitefly species, acetamiprid and acetamiprid+ethofenprox showed more than 92% mortality even at half of recommended concentrations. Acetamiprid and acetamiprid+ethofenprox showed both residual effect and systemic activity. In the control efficacy test on GWF and SWF, 90% control values were obtained at the 3th day after treatments of acetamiprid and acetamiprid + ethofenprox by application with recommended concentration. These results indicate that acetamiprid and acetamiprid+ethofenprox can be used in the control of the two whitefly species in field.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.133-136
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• 2002

Whitefly, Dialeuropora decempuncta (Quaintance rind Baker) (Homoptera: Aleyrodidae) has attained the major pest status in mulberry, causing 24% crop loss by sucking the leaf juice and manifesting leaf curl, chlorosis and sooty mould desease during monsoon season in West Bengal, India. The assessment of economic threshold revel is an essential component for formulating the management practices. Experiments were carried out by inoculating five different densities of whitefly viz.,10, 20, 30, 40 and 50 adults on covered mulberry plants in glass houses. From the findings, it was observed that irrespective of released density, no crop loss was observed in the initial period. But with the passing of days, the percent crop loss was increased rapidly. The linear relationship between percent crop loss and number of adults released was established to highlight the significance of economic threshold. The statistical analysis in the linear form of equation showed that initial population of 10, 20, 30, 40 and 50 whiteflies/plant causes 3%, 12%, 21%, 30% and 40% crop loss in a period of 28 days which is equivalent to 57 kg, 247 kg, 437 kg, 626 kg and 816 kg leaf/acre. Execution of management practices (spray of 0.01% monocrotophos) are economical to the farmer whenever the loss is above 247 kg/acre, but below which application of control measures is not economical. From this study, it can be inferred that the economic threshold level far whitefly is 20 individuals/plant beyond which a farmer has to take appropriate control measures.